107 



have a greater abundance of the catapleiite than of any other 

 mineral from Narsarsuk, with the exception of feldspar and 

 aegirite, while previously^) it had to be regarded as one of 

 the rare minerals from this locality. 



Two essentially different types have been found. 



1. Far the greater part of the material shows in most 

 relations, both crystallographic and physical ones, so great 

 conformity to Flink s catapleiite type 1, that it may most na- 

 turally be referred to this type, even if a few differences may 

 be pointed out, especially in the exterior. The crystalline 

 form is that described and figured by Flink, with the com- 

 bination (in the hexagonal system): c{000l}, г/{10Тз}, and 

 w{loTo}. The surfaces of c{000l} are very bright, although 

 not so completely plane as in the crystals previously known, 

 ^{lOls} is, as usually, bright directly at the base, while the 

 other part of it is completely opaque and gives generally no 

 reflections; it seems as if the lower part of the surface almost 

 always is curved somewhat downwards, so that it approaches 

 very much to о {10T2}; in some few of the smaller crystals, 

 where the surface is somewhat brighter than in the larger 

 ones, an almost continual series of reflections may be seen 

 in the goniometer to a distance from the base of 34 — 37"^, 

 while the theoretical angle of о{10Г2} is 38° 12'. Only in a 

 single specimen most of the crystals were provided with a more 

 steep pyramid also with completely opaque surfaces, which, by 

 the contact goniometer, may be determined to p{lOTl}. The 

 surfaces of m{l010} are as usually completely opaque, and 

 exceedingly rough and uneven. 



The diameter of the crystals varies from fractions af 1 mm 

 to 3 cm. Generally they are found crowded in large masses 



1) Comp. Flikk: M. 0. G. 24, 1901, p. 93. The catapleiite from Nar- 

 sarsuk has for the first time been described by Flink in Geol. Foren. 

 Förh. Stockholm, 15, 1893, p. 206, and in Zeitschr. f. Kr. 23, 1894, 

 p. 359. 



